Persistent pathology of the patent foramen ovale: a review of the literature

The efficacy and safety of patent Foramen Ovale Closure for Refractory Epilepsy (PFOC-RE): a prospectively randomized control trial of an innovative surgical therapy for refractory epilepsy patients with PFO of high-grade right-to-left shunt

BACKGROUND

A significant proportion of patients with epilepsy have an unknown etiology and lack effective targeted therapeutic drugs. Patent Foramen Ovale (PFO) induces hypoxia and microembolism, leading to cerebral neurological dysfunction and increased epilepsy risk. This study aims to assess the efficacy and safety of PFO closure for relieving epileptic seizures in patients with refractory epilepsy associated with PFO.

METHODS/DESIGN

Recruitment takes place at the West China Hospital of Sichuan University, China, for an open-label, randomized controlled clinical trial. The trial will include 110 patients with refractory epilepsy and PFO. Disease diagnoses will conform to the diagnostic criteria of the International League Against Epilepsy (ILAE) for refractory epilepsy and the American Society of Echocardiography (ASE) for PFO. Refractory epilepsy and high-grade right-to-left shunt (RLS) of the PFO will be further diagnosed using 24-hour video electroencephalogram and transthoracic echocardiography with contrast injection, respectively. Eligible participants require a secondary or higher volume of RLS.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (ChiCTR2200065681). Registered on November 11, 2022.

Machine learning in a real-world PFO study: analysis of data from multi-centers in China

PURPOSE

The association of patent foreman ovale (PFO) and cryptogenic stroke has been studied for years. Although device closure overall decreases the risk for recurrent stroke, treatment effects varied across different studies. In this study, we aimed to detect sub-clusters in post-closure PFO patients and identify potential predictors for adverse outcomes.

METHODS

We analyzed patients with embolic stroke of undetermined sources and PFO from 7 centers in China. Machine learning and Cox regression analysis were used.

RESULTS

Using unsupervised hierarchical clustering on principal components, two main clusters were identified and a total of 196 patients were included. The average age was 42.7 (12.37) years and 64.80% (127/196) were female. During a median follow-up of 739 days, 12 (6.9%) adverse events happened, including 6 (3.45%) recurrent stroke, 5 (2.87%) transient ischemic attack (TIA) and one death (0.6%). Compared to cluster 1 (n = 77, 39.20%), patients in cluster 2 (n = 119, 60.71%) were more likely to be male, had higher systolic and diastolic blood pressure, higher body mass index, lower high-density lipoprotein cholesterol and increased proportion of presence of atrial septal aneurysm. Using random forest survival (RFS) analysis, eight top ranking features were selected and used for prediction model construction. As a result, the RFS model outperformed the traditional Cox regression model (C-index: 0.87 vs. 0.54).

CONCLUSIONS

There were 2 main clusters in post-closure PFO patients. Traditional cardiovascular profiles remain top ranking predictors for future recurrence of stroke or TIA. However, whether maximizing the management of these factors would provide extra benefits warrants further investigations.